Model in scale 1:1. Corresponds to the dimensions of the manufacturer.
Materials set, textures included

Those who work in V-Ray versions lower than 3.1, be careful, in the materials in the BRDF section there is Microfaset GTR ( GGX ), if your version is older than 3.1, then the BRDF field will be empty. Choose Blinn, Phong or Ward - whichever suits you best

For Corona render, it is recommended to set the version to at least 7, since corona physical materials are used.